If you don't mind the question: How confident are /you/ in the existence of cats?
The reason I ask, is that I'm still trying to train myself to think of probability, evidence, confidence, and similar ideas logarithmically rather than linearly. 10 decibans of confidence means 90% odds, 20 decibans means 99%, 30 means 99.9%, and so on. However, 100% confidence in any proposition translates to an infinite number of decibans - requiring an infinite amount of evidence to achieve. So far, the largest amount of confidence given in the posts here is about 100 decibans... and there is a very large difference between '100 decibans' and 'infinite decibans'. And that difference has some consequences, in terms of edge cases of probability estimation with high-value consequences; which has practical implications in terms of game theory, and thus politics, and thus which actions to choose in certain situations. While the whole exercise may be a waste of time for you, I feel that it isn't for me.
How much evidence do you have that you can count accurately (or make a corect request to computer and interpret results correctly)? How much evidence that probability theory is a good description of events that seem random?
Once you get as much evidence for atomic theory as you have for the weaker of the two claims above, describing your degree of confidence requires more efforts than just naming a number.
How much confidence do you place in the scientific theory that ordinary matter is made of discrete units, or 'atoms', as opposed to being infinitely divisible?
More than 50%? 90%? 99%? 99.9%? 99.99%? 99.999%? More? If so, how much more? (If describing your answer in percentages is cumbersome, then feel free to use the logarithmic scale of decibans, where 10 decibans corresponds to 90% confidence, 20 to 99%, 30 to 99.9%, etc.)
This question freely acknowledges that there are aspects of physics which the atomic theory does not directly cover, such as conditions of extremely high energy. This question is primarily concerned with that portion of physics in which the atomic theory makes testable predictions.
This question also freely acknowledges that its current phrasing and presentation may not be the best possible to elicit answers from the LessWrong community, and will be happy to accept suggestions for improvement.
Edit: By 'atomic theory', this question refers to the century-plus-old theory. A reasonably accurate rewording is: "Do you believe 'H2O' is a meaningful description of water?".