“The leading modern cases on the application of the exclusivity test are Mallalieu v Drummond… and MacKinley (Inspector of Taxes) v Arthur Young McClelland Moores& Co… From these cases the following propositions may be derived. “(1) The words for the purposes of the trade mean to serve the purposes of the trade. They do not mean for the purposes of the taxpayer but for the purposes of the trade, which is a different concept. A fortiori they do not mean for the benefit of the taxpayer. “(2) To ascertain whether the payment was made for the purposes of the taxpayer’s trade it is necessary to discover his object in making the payment. Save in obvious cases which speak for themselves, this involves an inquiry into the taxpayer’s subjective intentions at the time of payment. “(3) The object of the taxpayer in making the payment must be distinguished from the effect of the payment. A payment may be made exclusively for the purposes of the trade even if it also secures a private benefit. This will be the case if the securing of the private benefit was not the object of the payment but merely a consequential and incidental effect of the payment. “(4) Although the taxpayer’s subjective intentions are determinative, these are not limited to the conscious motives which were in his mind at the time of the payment. Some consequences are so inevitably and inextricably involved in the payment that unless merely incidental they must be taken to be a purpose for which the payment was made. “To these propositions I would add one more, The question does not involve an inquiry of the taxpayer whether he consciously intended to obtain a trade or personal advantage by the payment, The primary inquiry is to ascertain what was the particular object of the taxpayer in making the payment,. Once that is ascertained, its characterisation as trade or private purpose is in my opinion a matter for the [tribunal] not the taxpayer.”