“The general scheme of section 29 [as it then was] is to exempt from liability to capital gains tax proceeds of sale of a person’s home. That was the broad conception. The justification for the exemption is that when a person sells his home he frequently needs to acquire a new home elsewhere. The evil of inflation was evident even in 1965. It must have occurred to the legislature that when a person sells his home to buy another one, he may well make a profit on the sale of one home and lose that profit, in effect, when he buys his new home at the new, inflated price. It would not therefore be surprising if Parliament formed the conclusion that, in such circumstances, it would be right to exempt the profit on the sale of the first home from the incidence of capital gains tax so that there is enough money to buy the new home.”