General principles for tax deductions

When can you deduct an expense? Section 11(a) contains the general principles

ONE OF the most-asked tax questions goes along the lines of “can I deduct xxx against my income?” There are two ways to answer this type of question.

One is to create a never-ending list of each and every type of deduction one could contemplate, together with its exceptions, circumstances under which such expense cannot be deducted, and so forth. The other is to explain the general principles that apply to claiming a particular expense as a deduction.

However, before one even gets down to the criteria for deductibility, there is an overriding principle: …