130 In relation to the bank, his Honour found, in effect, that the bank officers assumed that the then existing unlimited guarantees (ie, the Guarantees) which the bank held, which had been executed by the appellants to secure lending to Success, applied to secure the loans made to Success under the 2010 Loan Agreements.[89] As the evidence disclosed, there was only one such instrument held by the bank. The drawing of the inference that the bank officers assumed that this instrument, held by the bank, applied to secure the 2010 lending to Success did not logically depend upon any assumption about whether the bank officers had viewed the instrument or had its terms checked by lawyers at the time they made their assumption. The inference that the bank officers in fact assumed that the Guarantees applied to the bank's lending under the 2010 Loan Agreements to Success was open irrespective of their conduct (or, more accurately, absence of conduct) in that regard, even if it were thought to be 'careless'.[90] Also, even if the bank officers (and Ms Bazzo) could not explain in legal terms how the Guarantees applied to any lending under the 2010 Loan Agreements, that does not preclude a finding that such an assumption was actually made. In Waltons Stores, Deane J, in addressing the appellant's (the party estopped's) submission in that case that the buyers could not rationally have assumed that a binding agreement had been made for the sale of land without an exchange of contracts, said:[91]