Appeal No.3291­3294 of 2009, etc. Page 24 of 45forward of the loss of one year and setting off of the same against the profit or gains of the assessee from the same business in the subsequent year or years The crucial words, therefore, are “profits and gains of the assessee from the same business” i.e. the business in regard to which he sustained loss in the previous year. The question, therefore, is whether the securities formed part of the trading assets of the business and the income therefrom was income from the business. The answer to this question depends upon the scope of Section 6 of the Act. Section 6 of the Act classified taxable income under the following several heads : (i) salaries; (ii) interest on securities; (iii) income from property; (iv) profits and gains of business, profession or vocation; (v) income from other sources; and (vi) capital gains. The scheme of the Act is that income tax is one tax. Section 6 only classifies the taxable income under different heads