# Descartes vs Spinoza on Belief **URL:** \ **Category:** Philosophy of Mind\ **Created:** [October 27, 2026, 5:05am UTC](https://www.thephilosophyforum.com/t/descartes-vs-spinoza-on-belief/3790 "2026-10-27T05:05:23Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![isfandiyor](https://avatars.discourse-cdn.com/v4/letter/i/dfb087/32.png) [@isfandiyor](https://www.thephilosophyforum.com/u/isfandiyor)\ **Post date:** [October 27, 2026, 5:05am UTC](https://www.thephilosophyforum.com/t/descartes-vs-spinoza-on-belief/3790/1 "2026-10-27T05:05:23Z")
Answer this question: Do you agree that tigers are not herbivorous? Most probably to make sense of this sentence your mind had to picture a herbivorous tiger at first before rejecting that picture. For a moment you imagined a sentence with a false truth value and accepted it before calling it false. Rene Descartes believed that ideas are passive and neutral and believing involves an act of free will. The mind presents an idea, the will then accepts or rejects the idea. You decide to believe something or not. Baruch Spinoza had a contradicting view: comprehending ideas already involves automatic acceptance as truth. Meaning that as soon as you understand an idea you automatically accept it as truth. Psychology findings argue that the evidence favours the Spinozan model. For example, Daniel Gilbert in his paper ["How Mental Systems Believe”](https://kvond.wordpress.com/wp-content/uploads/2009/06/how-mental-systems-believe.pdf) argued that experimental evidence favors Spinoza. In 2015, philosophers Mandelbaum and Quilty-Dunn in “[Why Liberals Shouldn’t Watch Fox News](https://philarchive.org/archive/MANBWR)” extended the argument to the media, claiming that humans tend to accept a lot of information as true when they are under cognitive load. The key word in all of this is “overload”. When we have attention (our mental energy) to spare, we can catch the false claim and reject it, which is why the tiger sentence doesn’t fool anyone. The Spinozan model matters when there is mental overload. There may also be an evolutionary reason for this design. In the wild most of what you hear and see is true - where the water, the trees, the animals, which berries are poisonous and so on. Accepting first and doubting only when you can afford to is a mostly reliable strategy. The problem is that we now live in an environment where information is endless and cheap to produce. I believe there is something interesting about the Spinozan model: Attention is the scarce resource that doubt depends on. If accepting is the default and rejecting costs attention, then whatever consumes your attention has great influence over what you believe. If that is true, intellectual responsibility may be less about being a skeptical person and more about protecting the conditions under which skepticism is possible. This is relevant in our age, where we are constantly bombarded by information. **Why skepticism can’t protect you** One might say:”I can obviously understand a sentence without believing it.” and it would correspond to the Cartesian model. The answer to that is: the Spinozan claim isn’t that you end up believing the tiger is a herbivore. It’s that you accept it for a moment, then reject it so fast you never notice. Consider a study Mandelbaum and Quilty-Dunn describe. People read an account of a fire that first says paint cans were stored in a closet and then corrects itself: there were no flammable materials. Afterward, asked what caused the fire, many still blamed the paint cans, even though they could also tell you the report contained a correction but couldn’t remember what it was about. The article argues that under mental overload our capacity to assess all information is limited. If we automatically accept what we comprehend, then telling yourself “this source isn’t credible” is too late. By the time you’ve decided to reject it, the claim has already been comprehended and has started affecting your other beliefs. The authors add that even a lecture, about the best setting for careful listening, is full of mind-wandering. And when attention wanders, so does the ability to reject. That’s why attention is a resource. Rejecting costs it, and we spend it constantly without noticing. Another objection could be: “If your attention just gets drained by tickers, feeds, and wandering thoughts, then you’re not in control of it. Then it goes back to the question of free will. Either Descartes was right and we can choose to stop and assess the information or we don’t have control at all.” My answer is that we can’t control our attention at any moment but our environment we choose to expose ourselves to, what we read and what we scroll is something we can control. But I wonder if it might lead to its own echo chamber? Is there a way to avoid that?