But if it is so regarded, then by a process of comparison, and elimination, the common factor may be elicited, and a means afforded for arriving at a just conclusion.
It is true that from a logical standpoint, a bona fide offer of £1000 is just as good evidence the moment before acceptance as the moment after. Why, then, should one be received, and the other rejected? The answer is found in the same principle, namely, the better service to justice on the whole.
When the matter has reached the point of a concluded contract, there has been a definite concrete fact established, which not only evidences value, but to some extent helps to create or modify it. Where an owner has actually parted with his land for a fixed sum and a buyer has parted with his money for the land, a clear event has arisen, which, based on the ordinary instincts and impulses of human nature, indicates a consensus of opinion between two adverse parties in the community respecting the value of similar lands. Some advantage to justice is therefore manifestly possible from considering it, and the law presumes that up to that point the disadvantages of having to undertake the collateral inquiries as to comparison do not outweigh the possible advantages.
But if the negotiations do not end in a concluded bargain, the field is at once open to a multitude of other considerations before the same point of opinion is reached. Excursions into the realm of collateral circumstances would be endless. They would so add to the cost, delay and uncertainty of litigation as on the whole to render a great disservice to the cause of justice. The Court might have to inquire whether the owner or the other party really terminated the negotiations, and, if so, for what reason. Had either of the parties discovered the true worth of the property or been misinformed by some means as to its real value? Did the owner mistrust the ability of the purchaser, or did the latter find an adverse claimant to the property, or did his circumstances change, or was there a personal quarrel? Or did he learn of a still better bargain? Or, again, was the offer a sham on either side, or both sides? Such inquiries would render litigation intolerable, and defeat the purpose for which they were permitted.
Consequently, though the logical relevance may be the same when once the fact of a real firm offer is reached, whether it be accepted or not, yet to reach that point in the latter case is practically in such a different position in relation to the true function and aim of Courts of Justice, as to be placed legally in a different position also. The exception in favour of the indirect evidence ends where it fails to serve with advantage, and the line of demarcation is drawn at actual contract. This is in accord with the vast weight of authority, and finds support in text-books such as Best on Evidence (secs 92 and 93); Wigmore (secs 443-444); and Halsbury's Laws of England (vol XIII, par 625) (238-240).