According to Vatican Saying 59 (quoted below), if we eat too much it is not our stomach’s fault but our fault for having exaggerated ideas of how much our stomach needs.
This view is connected with the Epicurean doctrine of limits. The idea of limits is explained by a number of basic principles, which might be expressed as follows: (1) as living organisms we have needs and desires which we understand in terms of pleasure and pain; (2) for well-being and happiness we must satisfy our needs appropriately; (3) nature supplies what we need; (4) what we need is easy to get; (5) there are limits to what nature supplies; (6) there are limits to what we need; (7) we are inclined to desire too much; (8) accordingly we need to impose limits on our desires; (9) if we observe natural limits we can achieve settled pleasure and thus happiness; (10) if we desire too much (thinking that excess will give us happiness) we will cause ourselves unnecessary pain and distress (and thus bring on ourselves unhappiness).
Desires that do not accord with natural limits reflect ‘empty opinions’ or ‘false expectations’ (κεναὶ δόξαι). These are wrong conclusions that we can draw about our needs and resources. The evidence available to us is clear in nature, but we can form false opinions about it, and as a result give ourselves trouble and unhappiness. Philosophy enables us to interpret the evidence rationally and adjust our thoughts and behaviour to the demands of reality.
These questions are illuminated by a range of Epicurean sayings. Principal Doctrine 15 sums up the matter succinctly:
The wealth of nature is both limited and easily obtained; the wealth of false expectations goes on and on to infinity.
Other relevant sayings include: Principal Doctrines 3, 8, 10, 18, 20, 21, 22, 24; Vatican Sayings 21, 26, 29, 30, 33, 37, 68, 69, 71.
Thoughts for the Day, September 14: ‘It is not (as most people say) the stomach that is never satisfied, but an expectation – a false expectation – that an unlimited amount is needed to fill a stomach.’ (Vatican Sayings 59.)