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If you see inaccuracies in our content, please report the mistake via this form. To understand why, you need to know a bit about how the AI generates its answers. Large language models are extremely advanced word guessing machines. They take an input in the form of text, turn it into a string of numbers, and then use a huge statistical model to work out what the continuation is likely to be, one piece at a time. You can try out ChatGPT’s simplest features without creating an account, but to access features like the ability to save conversations for later, you’ll need an account. OpenAI recently released a standalone video app, called Sora 2, which immediately shot to the top of the app store after debuting.

Contents

Questions will continue to be routed to the most suitable model using GPT-5.1 Auto. GPT 5.1 Instant and Thinking are rolling out to users today, with paid Pro, Plus, Go, and Business users set to get access first, then free and logged-out users. Enterprise and limefx website Edu users will get a seven-day early-access toggle, after which GPT-5.1 will become the default model. According to a study commissioned by the BBC, ChatGPT is flawed in 81 percent of answers, with at least one serious error in a whopping 45 percent of all generated answers. Projects is a new addition that allows you to collect multiple chats on a particular topic in one place and get a bit more organized. It basically works like folders and you can use it for all sorts of categories.

Apple Debuts iPhone Pocket, a Limited Edition iPod Sock-Style Accessory

For deeper tasks, there’s Deep Research, which scours the web and creates full reports with citations, and Agent Mode, which can open sites, check your calendar, or pull data from connected apps like Gmail. But, because the approximation is presented in the form of grammatical text, which ChatGPT excels at creating, it’s usually acceptable. … It’s also a way to understand the “hallucinations”, or nonsensical answers to factual questions, to which large language models such as ChatGPT are all too prone. At the same time, its release prompted extensive media coverage and public debate about the nature of creativity and the future of knowledge work. Apart from models, there are modes and tools in ChatGPT that allow you to go beyond basic chatting. Each one is built for a specific task, from in-depth research to real-time browsing.

Once you’ve created a project, you can give it its own icon in any color to make it easier to find if you have many. For real power users, there’s also a Pro subscription, but it costs $200 a month. You get minimal restrictions, the highest possible speed of response, and access to experimental new features.

There are also desktop apps for Windows and macOS that add systemwide shortcuts for quickly launching ChatGPT and sharing your screen, files, or screenshots directly in a chat. Our comprehensive guide highlighting every major new addition in iOS 26, plus how-tos that walk you through using the new features. OpenAI plans to roll out GPT-5.1 gradually to keep performance stable, so not all users will see it right away. Since others have spent a lot of time finding such tricks, you can get a lot out of trying tips from videos, books, and articles. You can either create an old-fashioned account with an email address and password or log in with Google, Microsoft, or Apple to avoid having to remember another password.

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How to use ChatGPT

I’ve covered the models and modes above, but here’s a reminder of all the core features (as of October 2025). There’s even a Projects feature that keeps all your chats organized, plus a Library to manage all your generated images. Thanks to all these capabilities, people use ChatGPT for just about everything now — writing, brainstorming, translating, coding, studying, web searching, and shopping. The list goes on, and it’ll only continue as OpenAI rapidly updates its AI. For instance, it replaced GPT-4o with GPT-5 and, more recently, introduced Apps in ChatGPT, which lets you bring third-party services directly into your chats.

ChatGPT isn’t necessarily the “best” AI service out there (recent tests show other tools can outperform it in certain areas), but it’s the most widely known and the benchmark that all other services are compared to. ChatGPT includes a built-in image generator that’s powered by GPT-4o. It can take detailed prompts and produce realistic images in minutes. You can iterate on the results to fine-tune them and even export with a transparent background.

By default, GPT-5.1 Instant is warmer and more playful, and more likely to adhere to parameters that you set. GPT-5.1 Thinking is able to adapt thinking time more precisely to the question, and responses are clearer with fewer undefined terms. OpenAI today upgraded GPT-5 to GPT-5.1, the next-generation version of the AI model that powers ChatGPT. There are two versions of GPT-5.1, including Instant and Thinking. The goal of introducing AI is to save time, letting employees get more done, but in many cases they end up spending as much time fine-tuning their prompts as they previously spent doing the work themselves. Was the result you got from ChatGPT when you asked for something not very good?

OpenAI Launches Smarter, More Conversational ChatGPT 5.1

Then, if you get curious about features that require a subscription, try it out for a few months. If you end up liking it, consider switching to an annual subscription, as it will be cheaper in the long run. You can create your account in several ways, in the browser on your computer or in the ChatGPT app for iPhone or Android.

• Hardly anyone can have missed the AI phenomenon that has taken the world by storm.
• If you see inaccuracies in our content, please report the mistake via this form.
• According to a study commissioned by the BBC, ChatGPT is flawed in 81 percent of answers, with at least one serious error in a whopping 45 percent of all generated answers.
• ChatGPT isn’t like a noticeboard in a town square where anyone passing by can see what you’ve written.
• Just keep in mind that advanced features, history/memory, and higher limits require an account.

How to use ChatGPT: A beginner’s guide to the most popular AI chatbot

The basic idea is that some prompts, on average, lead to better answers. For example, adding a phrase like “now it’s time to think hard and rethink all assumptions” when brainstorming a problem can make ChatGPT’s response more creative. The latest reasoning models are better at solving equations, though it’s still easy to trick them into making mistakes on purpose, and some problems they completely miss.

• If you’re on the fence about which to choose, or want to know how to get started, this guide walks you through how to use ChatGPT.
• Experimentation should be fun and inspiring, but it’s easy to get carried away with fine-tuning.
• Since others have spent a lot of time finding such tricks, you can get a lot out of trying tips from videos, books, and articles.
• With pictures and videos, it’s easy to see whether the results are good or not, but with text it’s more difficult.

The less knowledgeable you are about a topic as a user, the less likely you are to spot errors and flaws in the AI-generated results yourself. That’s why you shouldn’t rely on what ChatGPT spits out without first checking more reliable sources. You can ask the chatbot to include links to sources and sometimes it will do so on its own, but it’s good to actually follow these and double-check. To get started, simply go to chatgpt.com or install the official app from the Apple App Store or Google Play. In my experience, the web version offers the fullest range of features available. ChatGPT is not the same AI chatbot that first burst onto the scene in 2022.

The AI wave took off when OpenAI released its chatbot ChatGPT, which gives large language models a conversational interface. Many competitors have emerged since then, from both small and large companies, but ChatGPT remains the most popular. You can try ChatGPT without an account in many regions, but signing in unlocks advanced features like saved chat history, conversation sharing, custom instructions, and higher usage limits.

If you prefer, you can talk to the ChatGPT instead of typing and reading the answers. The AI can recognize and respond in many languages, and you can choose your preferred spoken language in the settings. My recommendation is that you start exploring ChatGPT without paying.

Ask it to find, for example, the best humidifier available — and specify any features or a price range. Once you’ve chosen a model and even a mode or tool in ChatGPT, it’s time to finally ask something. Just type your question or request into the text box (or use the mic and speak). When you click through from our site to a retailer and buy a product or service, we may earn affiliate commissions.

For this guide, I have chosen the computer, but the app works the same way. Hardly anyone can have missed the AI phenomenon that has taken the world by storm. Politicians talk about how important it is not to “fall behind in the AI race,” and hundreds of millions have started using AI chatbots. It’s good, especially when you do a web search or deep research, and you can see sources, but it’s not perfect. Always fact-check important information and ask for links when possible.

It lets you turn text prompts into short, realistic video clips. OpenAI also formed a new partnership to bring Walmart and Sam’s Club products into ChatGPT through a “Buy in Chat” option using Instant Checkout. As of late 2025, GPT-5 Auto is the default model for most conversations. There’s still a free version of ChatGPT, but the Plus and Pro plans can do faster responses and provide access to the latest tools. If you’re on the fence about which to choose, or want to know how to get started, this guide walks you through how to use ChatGPT.

Most are found under the Tools menu (the + icon next to “Ask anything”) and come with usage limits per plan. Their responses come either from external sources (like a search) or from the data the model was trained on. The more accurate information about a topic that’s in the training data, the more likely the results will be correct, but errors can still creep in.

This year alone, OpenAI peppered us with new models, modes, and features to play with inside the AI. Our goal is to deliver the most accurate information and the most knowledgeable advice possible in order to help you make smarter buying decisions on tech gear and a wide array of products and services. Our editors thoroughly review and fact-check every article to ensure that our content meets the highest standards. If we have made an error or published misleading information, we will correct or clarify the article.

You need to have the ideas and the big picture, otherwise it’s easy to pancake. Many people now use AI instead of traditional search engines like Google. Google even shows “AI summaries” at the top of the search results, and many users likely read those instead of scrolling past. The interface of ChatGPT is simple, with a column on the left where you can find the different features and a list of past chats, and a main window on the right, where the chats themselves are displayed. As before, OpenAI has not disclosed technical details such as the exact number of parameters or the composition of its training dataset. GPT-5 was launched on August 7, 2025, and is publicly accessible through ChatGPT, Microsoft Copilot, and via OpenAI’s API.

Sophie Grégoire, Trudeau’s ex-wife, said in a post on Instagram on Monday she is “letting go” of “the people, the places, even the moments that once felt, I don’t know, infinite,” adding, “nothing we love is meant to be kept forever,” though she did not mention Trudeau by name. Perry also invited a fan onstage Monday night, who offered a faux marriage proposal to her, to which Perry said she wished he had asked her 48 hours earlier, a timeframe some noted was before the pictures of her and Trudeau on the yacht were published. The “Roar” singer and the Pirates of the Caribbean actor spent time together backstage at the one-man Los Angeles play The Absolute Brightness of Leonard Pelkey.

Two weeks later, Perry joined Bloom and his and his son Flynn (mom is Miranda Kerr) at a birthday party for Robert Downey Jr.’s son Exton. Katy Perry achieved mainstream success in 2008 with her single “I Kissed a Girl,” which became a number one hit in multiple countries. Her album One of the Boys (2008), featuring the hit “Hot N Cold,” sold more than three million copies in the United States. Perry added that her fans have joined her on the “rollercoaster” of her career and most recent album release, and thanked them for “the community we are and growing to become.” I lost my dad in the past year, and I feel that with grief also comes grace,” she said. The present moment and when we release what we cannot keep, we make space for the truth of connection, intimacy, the memory, for the lesson,” she continued.

On Monday night, octafx review the Roar singer took the stage at London’s O2 Arena and shared a little something about the kind of men she falls for. In the middle of the tour, the singer managed to find time for dates with Justin Trudeau. The singer, 40, broke her silence on what appeared to be a blossoming love between her and former Canadian Prime Minister Justin Trudeau. Trudeau was also spotted in the crowd at Perry’s sold-out Lifetimes tour in Canada. That same month, Perry posted her first photo of Bloom, showing the two sprawled out on the steps of the Hotel du Cap Eden-Rock, just miles away from the epicenter of the Cannes Film Festival.

• In the middle of the tour, the singer managed to find time for dates with Justin Trudeau.
• She rose to fame with One of the Boys (2008), a pop rock album containing her debut single “I Kissed a Girl” and follow-up single “Hot n Cold”, which reached number one and three on the U.S.
• Perry’s message received a stamp of approval from Gomez, who retweeted the post.
• Trudeau said in a statement in August 2023 that after “many meaningful and difficult conversations, we have made the decision to separate,” adding the two will focus on raising their three children together.
• The pop diva responded, saying her answer might have been different if the proposal had come a couple of days before.

The pop diva made a cheeky comment about the men she used to fall for during the concert

“She enjoys his company and thinks he is incredibly smart, but she was initially scared to get into anything so fast, or even at all, after her breakup and she was also focusing on her world tour,” they continued. When Katy and Justin first began hanging out, the singer was not looking to date anyone because she was “navigating too many things.” But they continued staying in touch. Katy Perry is currently on her Lifetimes world tour, which will conclude in December this year. Her cheeky comment came on the heels of Justin’s ex-wife Sophie Grégoire posting a cryptic message about “letting go” of love.

• She moved to Los Angeles at 17 to venture into secular music, and later adopted her stage name from her mother’s maiden name.
• The photos were reportedly taken off the coast of Santa Barbara, Calif., by an eagle-eyed tourist.
• Trudeau was married to Grégoire, a former television host and reporter, from 2005 to 2023.
• Representatives for the celebrities confirmed in July they had ended their nine-year relationship, which began in 2016 and continued after a brief split in 2017.
• Perry maintained her grip on the mainstream with her next release, Prism (2013), which produced, among other hits, the anthemic “Roar.” Her 2016 single “Rise” was featured in television coverage of that year’s Olympic Games in Rio de Janeiro.

Expand charts menu

With its bouncy, sharp-tongued second single, “Hot N Cold,” also proving popular, the album—much of which Perry wrote herself—eventually registered sales of more than three million copies in the United States. Katy Perry tied Michael Jackson’s record of five number one songs from a single album when her song “Last Friday Night (T.G.I.F.)” reached the top of the Billboard Hot 100 chart in 2011. Perry’s post included behind-the-scenes photos and videos of the making of the album and Perry rehearsing onstage for the Lifetimes Tour. The tour is an encapsulation of Perry’s discography, including smash hits like “Firework,” “The One That Got Away” and “California Gurls.” Perry split from her longtime partner, British actor Orlando Bloom, earlier this year. Representatives for the celebrities confirmed in July they had ended their nine-year relationship, which began in 2016 and continued after a brief split in 2017.

As the pair’s romance appeared to be heating up, Justin’s ex-wife Sophie shared a cryptic message on social media about letting go of love. Justin also attended the singer’s Lifetimes Tour concert at Montreal’s Bell Centre in July. The pop diva responded, saying her answer might have been different if the proposal had come a couple of days before.

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Perry maintained her grip on the mainstream with her next release, Prism (2013), which produced, among other hits, the anthemic “Roar.” Her 2016 single “Rise” was featured in television coverage of that year’s Olympic Games in Rio de Janeiro. Perry’s fifth studio album, Witness (2017), more introspective than her earlier work, was less well received. Perry later released 143(2024), which was notable for its negative reviews. “Records are snapshots of an artist trying to tell their story of where they are now or have been, and hope someone will hear themselves in some of the messages,” the post continued.

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The “Dark Horse” singer split from Orlando Bloom in June after nearly a decade together. The photos were reportedly taken off the coast of Santa Barbara, Calif., by an eagle-eyed tourist. In the photos, which were taken in September, the “Roar” singer, 40, wore a sleek one-piece swimsuit on the deck of the Caravelle while the former Canadian Prime Minister, 53, was just clad in a pair of jeans. Days before her birthday, Perry and Orlando attended the amfAR Gala Los Angeles 2018.

She is one of the best-selling music artists in history, having sold over 151 million records worldwide. Perry is known for her influence on pop music and her camp style, being dubbed the “Queen of Camp” by Vogue and Rolling Stone. The world’s highest-paid female musician in 2015 and 2018, Billboard named her one of the greatest pop stars of the 21st century. Perry’s initial efforts at mainstream stardom were fruitless, with two separate record labels signing and subsequently dropping her before any material was released.

Katy Hudson was raised in southern California, the middle child of two itinerant born-again Christian ministers. Nonreligious music was forbidden in the Hudson household, and she grew up singing church hymns and gospel tunes. As a teenager, she learned to play the guitar and sought a musical career in Nashville with a Christian record label, but her debut album, the gospel-influenced Katy Hudson (2001), sold poorly. By then, however, Hudson had found new musical models in such rock artists as Freddie Mercury and Alanis Morissette, whom she had discovered through friends. She soon moved to Los Angeles to pursue success in the secular music realm, adopting her mother’s maiden name, Perry, to avoid confusion with the actress Kate Hudson. Katheryn Elizabeth Hudson (born October 25, 1984), known professionally as Katy Perry, is an American singer, songwriter, and television personality.

Justin Trudeau romance with Katy Perry is ‘midlife crisis’ after marriage breakup: source

Katy Perry (real name Katheryn Hudson) was born and raised in Southern California. After recording the stripped-down live album MTV Unplugged (2009), Perry returned to the studio. At 16, Perry released a gospel album titled Katy Hudson (2001) under Red Hill Records, which was unsuccessful. She moved to Los Angeles at 17 to venture into secular music, and later adopted her stage name from her mother’s maiden name. Perry recorded an album while signed to Columbia Records, but was dropped before signing to Capitol Records. She rose to fame with One of the Boys (2008), a pop rock album containing her debut single “I Kissed a Girl” and follow-up single “Hot n Cold”, which reached number one and three on the U.S.

The pair kissed in one photo, with Justin cradling Katy’s backside in another. Following her marriage (2010–12) to Russell Brand, Perry became engaged to actor Orlando Bloom in 2018.

An example of adecision-rule is the EU rule, requiring that we maximise expectedutility in each decision-problem. Stefánsson and Bradley (2019) suggest yet another way ofaccounting for Allais’ preferences in decision theory is concerned with an extension ofJeffrey’s decision theory; this time extended to chancepropositions, that is, propositions describing objectiveprobability distributions. The general idea is that the desirabilityof a particular increase or decrease in the chance of someoutcome—for instance, in the Allais case, a 0.01 increase in thechance of the $0-outcome—might depend on what the chances werebefore the increase or decrease. But they suggest thatwhat explains Allais’ preferences is that the value of winingnothing from a chosen lottery partly depends on what would havehappened had one chosen differently. To accommodate this, they extendthe Boolean algebra in Jeffrey’s decision theory tocounterfactual propositions, and show that Jeffrey’sextended theory can represent the value-dependencies one often findsbetween counterfactual and actual outcomes. Others contendthat accounts of rational belief can and should be ultimatelyjustified on epistemic grounds; Joyce (1998), for instance, offers anon-pragmatic justification of probabilism that rests on the notion ofoverall accuracy of one’s beliefs.

Axiom 4

For instance, it may be that Bangkok isconsidered almost as desirable as Cardiff, but Amsterdam is a long waybehind Bangkok, relatively speaking. Or else perhaps Bangkok is onlymarginally better than Amsterdam, compared to the extent to whichCardiff is better than Bangkok. This kind of information about therelative distance between options, in terms of strength of preferenceor desirability, is precisely what is given by an interval-valuedutility function. Let \(S\) be afinite set of prospects, and \(\preceq\) a weak preference relation on\(S\). Then there is an ordinal utility function that represents\(\preceq\) just in case \(\preceq\) is complete and transitive. In our continuing investigation of rational preferences overprospects, the numerical representation (ormeasurement) of preference orderings will become important.The numerical measures in question are known as utilityfunctions.

Normative and descriptive

The vNM theorem is a very important result for measuring the strengthof a rational agent’s preferences over sure options (thelotteries effectively facilitate a cardinal measure over sureoptions). But this does not get us all the way to making rationaldecisions in the real world; we do not yet really have a decisiontheory. The theorem is limited to evaluating options that come with aprobability distribution over outcomes—a situation decisiontheorists and economists often describe as “choice underrisk” (Knight 1921).

Minimax Criterion

The content is designed for B.Com/M.Com students and emphasizes the logical framework necessary for making informed decisions under certainty and uncertainty. The interest in descriptive decision theory arose in parallel with the development of normative theories. Given the enormous influence axiomatic theories had in the academic community in the latter half of the twentieth century, it became natural to test the axioms in empirical studies. Since many decision theorists advocate (some version of) the expected utility principle, it is hardly surprising that the axioms of expected utility theory are the most researched ones. Early studies cast substantial doubt on the expected utility principle as an accurate description of how people actually choose.

Alternatives to probability theory

The subject includes rational choice theory, which seeks to formulate and justify the normative principles that govern optimal decision making, and descriptive choice theory, which aims to explain how human beings actually make decisions. Within both these areas one may distinguish individual decision theory, which concerns the choices of a single agent with specific goals and knowledge, and game theory, which deals with interactions among individuals. This entry will focus on rational choice theory for the single agent, but some descriptive results will be mentioned in passing. Yes, decision theory can be applied to personal life decisions, ranging from financial planning and career choices to more mundane daily choices. While the formal models and calculations used in corporate or policy decisions might be overwhelming for individual use, the principles can be adapted.

A common way to rationalise Allais’ preferences, is that in thefirst choice situation, the risk of ending up with nothing when onecould have had $2400 for sure does not justify the increased chance ofa higher prize. In the second choice situation, however, the minimumone stands to gain is $0 no matter which choice one makes. Therefore,in that case many people do think that the slight extra risk of $0 isworth the chance of a better prize. Thenthere is an ordinal utility function that represents \(\preceq\) justin case \(\preceq\) is complete and transitive. Let us nonetheless proceed by first introducing basic candidateproperties of (rational) preference over options and only afterwardsturning to questions of interpretation. As noted above, preferenceconcerns the comparison of options; it is a relation between options.For a domain of options we speak of an agent’s preferenceordering, this being the ordering of options that is generated bythe agent’s preference between any two options in thatdomain.

For personal decisions, simple weighted lists of pros and cons, considering different outcomes and their likelihoods, can help individuals make more considered and rational choices. Let us conclude by summarising the main reasons why decision theory,as described above, is of philosophical interest. First, normativedecision theory is clearly a (minimal) theory of practicalrationality. The aim is to characterise the attitudes of agents whoare practically rational, and various (static and sequential)arguments are typically made to show that certain practical setbacksbefall agents who do not satisfy standard decision-theoreticconstraints. Under the assumption that an ethical choice must berational, the findings of decision theory have implications forethics, or more generally, for the ways in which we can valuestates of affairs.

Richard Jeffrey’s theory, whichwill be discussed next, avoids all of the problems that have beendiscussed so far. Another way to put this is that, when the above holds, the preferencerelation can be represented as maximising utility, asmeasured by u, since it always favours an option with higherutility. Illustrates decision trees as a visual decision-making tool, demonstrating an example involving insurance decision under uncertain fire risk.View Overview of Decision Theory focusing on decision making process amid uncertainty, Bayesian analysis, and the steps involved in decision making.View

These shapes are linked with arrows or arcs in specific ways to show the relationship among the elements. Figure 10.2 shows an example for making a decision regarding Vacation Activity (decision node). Weather Forecast and Weather Condition are random nodes namely uncertain events while Satisfaction is a value node which is a result of the decision. The elements of decision theory are a set of possible future conditions that can exist that will have affect the results of the decision, a list of possible alternatives to choose from and a calculated or known payoff for each of the possible alternatives under each of the possible future conditions. Decision analysis provides a “framework for analyzing a wide variety of management models”.

Addressing these challenges requires a combination of analytical rigor and awareness of human behavior, ensuring that decisions are both informed and aligned with the decision-maker’s objectives. Bayesian Decision Theory incorporates Bayes’ theorem to update the probabilities of outcomes as new information becomes available. This approach allows decision-makers to refine their assessments and improve their choices over time. By integrating prior knowledge with observed data, Bayesian methods facilitate more informed decision-making, particularly in dynamic environments where conditions may change rapidly.

Independence and the Sure-Thing Principle

• AI technologies such as machine learning, natural language processing, and computer vision are trusted aspects of business today, used to increase profits and reach set goals.
• This evolution will enhance the ability to model complex decision problems and improve the accuracy of predictions.
• While the principle is often defended as adecision-rule (see, e.g., Steel 2014), some think that anysuch interpretation of the principle is implausible (Peterson 2006,Stefánsson 2019).
• This approach has recently beenquestioned in the context of climate policy, where so-calledintegrated assessment models have been criticised for theirreliance on EU theory (see, for instance Pindyck 2022 and Stern et. al2022).
• But whether or notthe preference in question should be explained by the potential forregret, it would seem that the desirability of the $0-outcome dependson what could (or would) otherwise have been; in violation of theaforementioned assumption of separability.

In the context of climate policy, Continuity implies thatno climate catastrophe is so bad that we shouldn’t be willing toimplement a policy that might (with low probability) result in thatcatastrophe as long as the policy is sufficiently likely to insteadresult in some social gain. So under what conditions can a preference relation \(\preceq\) on theset \(\Omega\) be represented as maximising desirability? Some of therequired conditions on preference should be familiar by now and willnot be discussed further. In particular, \(\preceq\) has to betransitive, complete and continuous (recall our discussion in Section 2.3 of vNM’s Continuity preference axiom).

• A recently defended complete decision theory without Continuity is thelexicographic utility theory.
• Start with the Completeness axiom, which says that an agent cancompare, in terms of the weak preference relation, all pairs ofoptions in \(S\).
• More specifically, decision theory deals with methods for determining the optimal course of action when a number of alternatives are available and their consequences cannot be forecasted with certainty.
• More generally, although people rarelythink of it this way, they constantly take gambles that have minusculechances of leading to imminent death, and correspondingly very highchances of some modest reward.
• At the far end of the spectrum is theposition that the very meaning of belief involves preference.

2 On completeness: Vague beliefs and desires

If this were not the case, the axiom ofState Neutrality, for instance, would be a very implausiblerationality constraint. Suppose we are, for example, wondering whetherto buy cocoa or lemonade for the weekend, and assume that how good wefind each option depends on what the weather will be like. For if we do not, the desirability of the outcomes willdepend on what state is actual. Since lemonade is, let us suppose,better on hot days than cold, an outcome like “I drink lemonadethis weekend” would be more or less desirable depending onwhether it occurs in a state where it is hot or cold.