The theory of 4 humors as the reason for diseases and illnesses in the seventeenth century changed completely because science advanced and the existence and nature of microbes were discovered.
In the period above, medical experts usually looked at sicknesses and diseases from the paradigm of the theory of 4 humors. These basically were the major fluids in the body namely:
The theory states that these fluids must be balanced and in adequate amounts, for one to remain healthy.
This line of thought was expunged when microbes and their capacity to cause illnesses were discovered.
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