How confident are you in the Atomic Theory of Matter?

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?”.