For the purposes of this Act a person's estate is the aggregate of all the property to which he is beneficially entitled, except that the estate of a person immediately before his death does not include excluded property.

A person who has a general power which enables him, or would if he were sui juris enable him, to dispose of any property other than settled property, or to charge money on any property other than settled property, shall be treated as beneficially entitled to the property or money; and for this purpose " general power" means a power or authority enabling the person by whom it is exercisable to appoint or dispose of property as he thinks fit.

In determining the value of a person's estate at any time his liabilities at that time shall be taken into account, except as otherwise provided by this Act.

The liabilities to be taken into account in determining the value of a transferor's estate immediately after a transfer of value include his liability for capital transfer tax on the value transferred but not his liability (if any) for any other tax or duty resulting from the transfer.

Except in the case of a liability imposed by law, a liability incurred by a transferor shall be taken into account only to the extent that it was incurred for a consideration in money or money's worth.